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981.
Two- and three-dimensional Ising-type systems are considered in the finite-cross-section cylindrical geometry. An interface is forced along the cylinder (strip in 2d) by the antiperiodic or +– boundary conditions. Detailed predictions are presented for the largest asymptotically degenerate set of the transfer matrix eigenvalues. For rough interfaces, i.e., for 0<T<T
c in 2d,T
R<T<T
c in 3d, the eigenvalues are split algebraically, and the spectral gaps are governed by thesurface stiffness coefficient. For rigid interfaces, i.e., 0<T<T
R in 3d, the eigenvalues are split exponentially, with the gaps determined by thestep free energy. 相似文献
982.
B. Orel U. Opara Krašovec U. Lavrenčič Štangar P. Judeinstein 《Journal of Sol-Gel Science and Technology》1998,11(1):87-104
This paper reports on the development of all sol-gel EC devices, having the configuration WO3/ormolyte/SnO2:Mo, WO3/ormolyte/SnO2:Sb and WO3/ormolyte/SnO2:Sb:Mo, where all three internal layers, including the ionically conductive inorganic-organic hybrid (ormolyte), are prepared via the sol-gel route. The electrochemical and optical properties of EC devices are presented and their cycling stability and reversibility of their optical modulation assessed. The transmission modulation of the devices depends on the thickness of the active electrochromic, counter-electrode and ormolyte layer. The electrochemical and optical properties of individual films and the structural properties of the ormolyte are described and correlated with the stability of the all sol-gel EC devices. 相似文献
983.
Experimental data on
0 meson polarization in
–
p reaction at 5 GeV/c are presented. Change in
0 meson polarization for mesons produced at smallP
2
and atP
2
0·3 or produced in backward direction in CMS is demonstrated. Natural explanation of these phenomena is one pion exchange mechanism and mechanism of quark-antiquark annihilation as observed for
0 meson production in¯pp reactions.The authors are indebted to Ján Piút, Richard Lednický, V. S. Rumiancev and N. K. Koutsidi for discussions and critical comments. 相似文献
984.
Ronan Baron Biljana Šljukić Chris Salter Alison Crossley Richard G. Compton 《Electroanalysis》2007,19(10):1062-1068
The combinatorial screening of different metallic nanoparticles as electrocatalysts was investigated and efficiently applied for the detection of hydrazine. In a first step, glassy carbon microspheres decorated with metallic nanoparticles (Au, Pd, and Ag) were abrasively attached on the surface of a basal plane pyrolytic electrode giving a ‘multi–metal’ nanoarray. In a second step, electrodes modified with only one type of metallic nanoparticles allowed the identification of Pd as the unique catalytic material. In addition, a carbon‐epoxy composite electrode loaded with the Pd nanoparticles was then constructed for a practical use. The carbon‐epoxy composite nanoarray electrode was found to have excellent characteristics as for the sensing of hydrazine with a limit of detection of 2 μM. 相似文献
985.
The influence of the temperature and time of heating during dissolution on the aging of concentrated aqueous solutions of poly(vinyl alcohol) and aging at different temperatures are described. Changes occuring during aging are interpreted on the basis of non-Newtonian viscosity and normal stress measurements. 相似文献
986.
M. Dermelj Z. Šlejkovec P. Stegnar V. Čoh K. Čujes M. Novič 《Journal of Radioanalytical and Nuclear Chemistry》1992,164(1):59-69
On the basis of tracer experiments, a simple and rapid radiochemical separation method for simultaneous determination of I–, Br– and Cl– in one aliquot of a water sample (only 2–4 ml) has been developed. The method is based on short irradiation of the water sample and separation of the halogens using sequential ion exchange columns filled with Dowex 1×8, 100–200 mesh anionic resin prepared in I–/I2, Br–/Br2 and Cl– form. After washing the columns with an appropriate volume of 2% NaCl solution, the resins were transferred to vials and activities of the isolated radionuclides128I,82Br and38Cl measured together with standards in a well type or on a coaxial Ge detector connected to a Canberra 90 multichannel analyzer. Besides high chemical yields, from the -spectra of the isolated radionuclides, it is evident that high decontamination fac-The paper was presented at the MTAA-8, Vienna, September 1991. 相似文献
987.
The modified valence force field and the potential energy distribution were calculated for adducts of mono-, di-, and trichloroacetic acids with dimethyl sulphoxide. The calculated force constants gave a good fit to the experimental frequencies of normal adducts and their OD and CD3 analogues. The hydrogen bond strength increases from mono- to trichloroacetic acid and this is reflected in the decrease of the KO-H force constant and increase of kO?h. 相似文献
988.
A small library of H-pin polyamides with variable aliphatic bridge lengths (CH(2))(n)(), where n = 4-8, connecting a central Py/Py pair was prepared via parallel synthesis with Ru-catalyzed alkene metathesis on solid phase as a complexity-generating cross-linking reaction. DNA binding affinities and sequence specificities were analyzed for each member of the library to determine the optimum linker length. An H-pin polyamide with a six-methylene bridge was found to have the highest affinity to its match site with high selectivity over a 1-bp mismatch site. The relationship between the number of methylenes in the linker (CH(2))(n)() and affinity is n = 6 > 4 > 7 > 5 > 8. These results indicate that 6 followed by 4 methylene-bridged polyamides represent the optimum spacer length for the H-pin motif in the DNA minor groove. Importantly, the H-pin is competitive with hairpin polyamides with respect to affinity and specificity. The metathesis-based convergent synthetic route to H-pin polyamides expands the scope of readily available DNA recognition motifs for small molecule-based gene regulation studies. 相似文献
989.
Summary The influence of the alcohol content of the mobile phase and water, acetic acid and aniline as mobile phase additives on the
generation and shape of two additional changes of the streaming current, generated inside the liquid chromatography column
by injection of any sample and recorded before the responses of retained solutes, was studied in a normal-phase system using
silica gel as the stationary phase. The mobile phases were based on a n-heptane-1-propanol mixtures. Under the same conditions
the relationships between the column interparticle volume, the column void volume and the total liquid volume in the column
and the retention volumes of these two streaming current responses, having the form of chromatographic peaks, were studied.
The column void volume was identified with the retention volume of n-octane. The total liquid volume in the column (column
hold-up) was calculated from the weight loss of the column wetted with water at first and then dried in nitrogen stream.
The retention volume of the first streaming current response equals the column interparticle volume disregarding the mobile
phase composition. If the 95∶5 n-heptane-1-propanol mobile phase contains water up to 80% of its saturated concentration (up
to 0.114% by vol.), the retention volume of the second response agrees with the total volume of the liquid in the silica gel
column, with a precision better than 2%. At a higher relative water saturation the retention volume of the second response
increases, while the column void volume decreases. Both changes are explained by the spontaneous formation of a highly polar
stagnant liquid in the pores of the silica gel. 相似文献
990.
In treating the vibrational spectra of crystallohydrates, it is usually assumed that the water molecules vibrate independently (or nearly so) from the rest of the structural units and, consequently, the bands which shift on deuteration are automatically assigned to water modes (internal or external). In a number of hydrates of metal carboxylates, however, we were able to detect indications of water-anion vibrational coupling. 相似文献